• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.223-226
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• 1999

A bacterial strain producing high level of an extracellular phytase was isolated from cooked rice and identified as a strain of Bacillus sp. and designated as Bacillus sp. KHU-10. Optimum culture conditions were investigated for the maximum productivity of phytase by Bacillus sp. KHU-10. 1.0% Maltose and 1.0% peptone with 0.5% beef extract were the best carbon source and nitrogen source, respectively. The addition of $CaCl_2$, stimulated the enzyme productivity with concentration between 0.01% and 0.2%, in the medium. Although sodium phosphate increased the cell mass, the enzyme activity decreased. Calcium phytate and wheat bran containing phytate did not enhance the enzyme production. Under the optimum medium, the production of the phytase reached the highest level of 0.2 unit/ml after 4 days of incubation.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.383-390
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• 2010

A newly isolated active producer of raw-starch-digesting amyloytic enzymes, Rhizopus microsporus var. chinensis CICIM-CU F0088, was screened and identified by morphological characteristics and molecular phylogenetic analyses. This fungus was isolated from the soil of Chinese glue pudding mill, and produced high levels of amylolytic activity under solid-state fermentation with supplementation of starch and wheat bran. Results of thin-layer chromatography showed there are two kinds of amyloytic enzymes formed by this strain, including one $\alpha$-amylase and two glucoamylases. It was found in the electron microscope experiments that the two glucoamylases can digest raw corn starch and have an optimal temperature of $70^{\circ}C$. These results signified that amyloytic enzymes secreted by strain Rhizopus microsporus var. chinensis CICIM-CU F0088 were types of thermostable amyloytic enzymes and able to digest raw corn starch.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.253-259
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• 2010

In vitro and in vivo mycofumigation effects of the volatileproducing fungus Nodulisporium sp. CF016 isolated from stem of Cinnamomum loureirii and the role of its volatile compounds were investigated against phytopathogenic fungi. The volatile compounds produced by Nodulisporium sp. CF016 inhibited and killed a wide range of plant and storage pathogens including to Pythium ultimum, Rhizoctonia solani, Fusarium oxysporum, Phytophthora capsici, Sclerotinia sclerotiorum, Colletotrichum coccodes, Magnaporthe oryzae, Alternaria panax, Botrytis cinerea and Penicillium expansum. Mycofumigation with wheat bran-rice hull cultures of Nodulisporium sp. CF016 showed in vivo antifungal activity against gray mold caused by B. cinerea and blue mold caused by P. expansum of apple. The most abundant volatile compound produced by Nodulisporium sp. CF016 was $\beta$-elemene followed by 1-methyl-1,4-cyclohexadiene, $\beta$-selinene and $\alpha$-selinene. Nodulisporium sp. CF016 could be an attractive mycofumigant in controlling postharvest diseases of various fruits including apple.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1385-1392
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• 2009

This work evaluates the effect of different amino acids on production of Cyclosporin (CyA) production in solid-state fermentation that was previously optimized for different fermentation parameters by one factor at-a-time for the maximum production of CyA by Tolypocladium inflatum MTCC557. Based on the Plackett-Burman design, glycerol, ammonium sulfate, $FeCl_3$, and inoculum size were selected for further optimization by response surface methodology (RSM). After identifying effective nutrients, RSM was used to develop mathematical model equations, study responses, and establish the optimum concentrations of the key nutrients for higher CyA production. It was observed that supplementation of medium containing (% w/w) glycerol, 1.53; ammonium sulfate, 0.95; $FeCl_3$, 0.18; and inoculum size 6.4 ml/5g yielded a maximum of 7,106 mg/kg as compared with 6,480 mg CyA/kg substrate using one factor at-a-time. In the second step, the effect of amino acids on the production of CyA was studied. Addition of $_L$-valine and $_L$-leucine in combination after 20 h of fermentation resulted in maximum production of 8,166 mg/kg.

• KSBB Journal
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• v.9 no.5
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• pp.499-505
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• 1994

Bacillus macerans cyclodextrin glucanotransferase(EC 2.4.1.19: 1, 4-${\alpha}$-D(1, 4-${\alpha}$-glucano)-transferase, CGTase) was purified by the technique of starch adsorption and DEAE-cellulose column chromatography. The molecular weight of the enzyme was 67,000, consisting of a subunit. The enzyme converted starch into ${\alpha}$-, ${\beta}$-, and ${\gamma}$-CD in the relative amounts of 1:1.68:0.32, respectively. In the early reaction period, maltohexose was formed mainly by the coupling reaction of ${\alpha}$-CD with D-glucose and then other oligosaccharides. Maltotetrose was formed mainly from ${\alpha}$-CD in the initial stage of hydrolysis of the enzyme and then small amount of other oligosaccharides. Maltotriose was a good substrate for the enzyme and maltosyl or D-glucopyranosyl group can be transfered from this sugar. In this work, D-glutosyl transfer was premiered.

• Journal of Microbiology
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• v.44 no.3
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• pp.276-283
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• 2006

The thermophilic fungus Thermoascus aurantiacus 179-5 produced large quantities of a glucosidase which preferentially hydrolyzed maltose over starch. Enzyme production was high in submerged fermentation, with a maximal activity of 30 U/ml after 336 h of fermentation. In solid-state fermentation, the activity of the enzyme was 22 U/ml at 144 h in medium containing wheat bran and 5.8 U/ml at 48 h when cassava pulp was used as the culture medium. The enzyme was specific for maltose, very slowly hydrolyzed starch, dextrins (2-7G) and the synthetic substrate (${\alpha}$-PNPG), and did not hydrolyze sucrose. These properties suggest that the enzyme is a type II ${\alpha}$-glucosidase. The optimum temperature of the enzyme was $70^{\circ}C$. In addition, the enzyme was highly thermostable (100% stability for 10 h at $60^{\circ}C$ and a half-life of 15 min at $80^{\circ}C$), and stable within a wide pH range.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.38-45
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• 1998

To extract insoluble proteins and to improve funtional properties of abolished proteins, an phytase producing Aspergillus sp. SM-15 was isolated from soil. The enzyme was purified and its enzymological characteristics were investigated. Phytase production reached to maximum when the wheat bran medium containing 1% mannose, 1% yeast extract, 1% (NH4)2HPO4 and 0.2% calcium chloride was cultured for 4 days. Phytase was purified 17.1 fold and specific activity was 244.32unit/mg by a sequencial process of ammonium sulfate fraction, ion exchange chromatography and gel filtrations Pruified enzyme was confirmed as a single band by the polyacrylamide gel electro-phoresis. The molecular weight of phytase was estimated to be 46,000. The optimum pH and temperature for the phytase activity were 5.5 and 5$0^{\circ}C$. The enzyme is stable in pH 4.5~5.5, 6$0^{\circ}C$. The activity of purified enzyme was inhibited by Hg2+ whereas activited by Pb2+ and Fe2+. The activity of phytase was inhibited by the treatment with iodine. The result indicate the possible involvement of histidine at active site. Km and Vmax of the puridied phytase were 37.037mM/L and 159.87umol/min, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.120-124
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• 1994

Nine wind vegetables were analyzed for moisture, ash, crude protein, crude lipid and dietary fiber. Wild vegetables contained 33-53% of dietary fiber on a dry weight basis. Dalle (Allium monanthum) contained 49% total dietary fiber and 22% soluble dietary fiber and dodok(Codonopsis lanceolata) contained 55% total dietary fiber and 21% soluble dietary fiber. Wild 8% more dietary fiber than cultivated one. Water holding capacities of wild vegetables were higher than commercial wheat bran and soy fiber, but lower in oil absorption. When wild dodok and dalle were wet milled by blade grinding before sieving the dietary fiber content in dodok was increased from 55 to 83 % with increasing the dietary fiber content in dalle form 49% to 69%.

• Asian Journal of Turfgrass Science
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• v.13 no.4
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• pp.223-234
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• 1999

Antibiotic activity of selected biocontrol agent Trichoderma harzianum ABGS-95 showed 59% to P. graminicola, 65% to P. aphanidermatum and 57% to Rhizoctonia solani compare to non-treated control. ABGC-95 showed resistant to major agrochemicals such as metalaxyl+mancozeb, etridiazole, propamocarb, toclofos methly, terbuconazole, pencycuron and flutolanil. The biocontrol agent T. harzianum ABGC-95 grew vigorously in low nutrient media and water agar. And sand mixture with wheat bran or mowing debris of zoysia grass also provided good growth of the organism. Application of sand mixture of Trichoderma spp. into aeration cores in golf showed most effective biocontrol of pythium blight. Top dressing application of T. harzianum ABGC-95 reached 83% control efficient while spray application of same biocontrol agent showed only 69% control. The biocontrol agent ABGC-95 successfully suppressed the population density of Pythium spp. in soil. The population density of total Pythium spp. in ABGC-95 treated soil was sustained almost same population at beginning(early May) up to end of August, while the population in untreated control plot was increased 5 times that of beginning and even 10 times in pathogen accumulated soil.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.570-577
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• 1995

Aspergillus sp. SB-2704 was selected for its strong polygalacturonase activity among various strain of mold found in soil. It was found that production of polygalacturonase reached to maximum when the wheat bran medium containing 1% polypepton, 1% glucose, and 0.2% FeSO4 were cultured for 3 days at 35$^{\circ}C$. Polygalacturonase was purified 20.90 fold from Aspergillus SB-2704. The purification procedures include ammonium sulfate treatment, gel filtration on Sephdex G-150 and DEAE-cellulose ion exchange chromatography. Yield of the enzyme purification was 4.34%. Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. When the purified enzyme was applied to SDS-polyacrylamide gel electrophoresis, the molecular weight was estimated to be 36,000. The optimum pH for the enzyme activity was 5.5 and optimum temperature was 5$0^{\circ}C$. The enzyme is stable in acidic condition. The activity of purified enzyme was inhibited by Pb2+, Hg2+ and Ba2+, whereas activated by Cu2+, Mn2+, Mg2+ and Fe2+. The activity of polygalacturonase was inhibited by the treament wit maleic anhydride, iodine, and EDTA. The result indicate the possible involvement of histidine and metal ion at active site.